1. Field of the Invention
This invention relates to a mop to be used for dusting floor surfaces and other solid surfaces. More particularly, the invention relates to a mop having a prominently improved cleaning effect and an excellent washing resistance in combination.
2. The description of the Prior Art
In principle, mops are composed of tuft-like piles and a substrate cloth to which the piles are fixed.
In general, such mops are prepared by cutting thick folded yarns in appropriate uniform lengths and sewing the central portions of the yarns to the substrate cloth by tufting thick folded yarns on the substrate cloth simultaneously cutting them in appropriate uniform lengths. Accordingly, in many cases, the cut ends of the piles are left untreated after cutting.
The function of the mop depends essentially on properties and activities of piles cut into tufts having a uniform length. The most fatal defect of the conventional mops resides in that resistance of such piles aainst the external force imposed at the washing treatment is extremely low and they are untwisted instantaneously at the washing treatment, with the result of that the piles are frayed out into individual yarns or constituent fiber groups, and they are entangled with each other yielding a large quantity of yarn wastes. Accordingly, the conventional mops are greatly worn away by the washing treatment and as detailed hereinafter, the function as the dusting mop is drastically degraded. This invention intends to overcome this defect involved in the conventional mops and provides a mop excellent in both the washing resistance and the dusting effect by fixing twisted form of the yarn.
The term "yarn" used in the instant specification and claims is meant a thick fiber bundle formed by folding a number of thick single yarns. For instance, several thick single yarns of count No. 1, 2 or 3 are folded to form such yarn. The apparent diameter of the yarn is as great as about 2 to about 10 mm, and thus, the yarn used in this invention is special one of a greater size that is not seen among ordinary weaving yarns and sewing yarns. Such yarn is a product formed especially for use in preparing mops. In this invention, the term "pile" is used to indicate such yarn fixed in the mop-head, and the term "yarn" is used only to indicate the raw material yarn ready for use of making mops.
As the fibrous material of the yarn there are generally employed cotton fibers or mixed cotton fibers with a small amount of cellulosic chemical fibers such as rayon or acetate fibers and/or synthetic fibers such as polyester, vinylon, nylon and acrylic fibers, etc. It has long been known that such yarns of cotton fibers and yarns composed mainly of cotton fibers lack by nature in the twist-setting property, and when they are subjected to the washing treatment, their twists are quickly released expandingly from their cut ends and are frayed in disorder yielding a large quantity of yarn wastes, resulting in a great loss.
Such fraying of pile results in not only a quantitative loss brought about by yarn wastes frayed apart from the pile but also a qualitative loss of deteriorating mop function. More specifically, the untwisted piles fall into entangling and come to take an appearance resembling a fiber mass. Advantages of mops over plain fabrics are owing to a large surface area brought about by individual and independent piles and to three-dimensional movements of these piles. Accordingly, if their form is changed into one resembling a fiber mass, the surface area is drastically decreased and the advantages brought about by the three-dimensional movements of piles is entirely lost. And thus, the dusting efficiency of such mop is low down to a level attainable by woven fabrics.
At present, a large quantities of mops are made for dusting utilization. Aabove all, with the recent development of the dry maintenance techniques, utilization of mops impregnated with a special oil composition for absorbing dusts thereon prevails rapidly. Further, since such oil-treated mops become available under the rental system, they have been used in ordinary households and demands for them have been rapidly increasing.
In general, these rental mops are recovered after they have been rented to users for a certain prescribed period, and washed for re-use; this cycle is repeated. The regeneration of such used mops being extremely soiled with adsorbed dirt is necessitate to perform a very effective washing under severe conditions as not conceivable from the general concept of laundry, that is, using a large amounts of detergents and washed by means of a so-called beating method in a large rotary washing machine for industrial uses. Furthermore, the intended cleanness is frequently unattainable unless such washing procedure is repeated. The increase of frequency of regeneration of used mops by such washing procedure will reduce the cost of rental products, resulting in reduction of the economical burden on users. However, this frequency of regeneration of used mops should naturally be controlled by the washing resistance of the mops, i.e., the washing resistance of piles.
It has been well known that the improvement of the washing resistance of piles will be attained by preventing untwisting of piles from their cut-ends, and various methods have been proposed and practised to prevent fraying of piles. However, no satisfactory method has yet been developed. For instance, various resin-processing methods have been tried to fix the twisted form of piles by fiber-to-fiber bonding, but according to such methods, the pliability and mobility of piles are rather degraded and the fraying-preventive effect is not so conspicuously improved, whatever kinds of resins are employed for processing. Further, the tensile strength of the pile is rather lowered by the resin processing. Thus, the mop-pile which have the faculty of keeping their twisted form stably against washing action have long been searched for in the mop industry.
As a result of close examinations of fraying of mop piles caused by the washing action in water, we found that the formation of yarn wastes is not caused by breakages of cotton fibers but by slippages among fibers. More specifically, it was found that the constituent fibers of the piles are pulled apart or separated from the piles during the washing treatment, resulting in formation of yarn wastes. It was also found that such phenomenon is caused to occur regardless of short or long staples of the constituent fibers.
Based on such analysis of the fraying phenomenon of mop piles, we have made various investigations, and have now found that the yarn composed of cotton or mainly of cotton fibers can be set up to retain an excellent washing resistance when they have a soft twist just within a specific range of twist number and are mercerized under specific conditions detailed hereinafter; and by employing such specifically treated yarns, there can be obtained a novel mop having a highly improved washing resistance and an excellent dusting efficiency in combination.